The invention relates to a rotary conveyor making it possible to move containers, such as bottles in stepwise manner past a certain number of fixed stations. The invention also relates to the application of such a conveyor to the construction of an automated installation for taking liquid samples from bottles sealed by caps with a view to analyzing these samples.
The performance of certain chemical processes makes it necessary to periodically take samples of products at different stages of the process, in order to analyze them to check their characteristics.
In the nuclear industry, these sampling operations are complicated by the fact that they have to be carried out within glove boxes or shielded enclosures ensuring the protection of the personnel located outside the same.
When the sampling operations involve occasional checks performed in the laboratory, use is presently made of glass pipettes having a spherical ground joint connected to a syringe in their upper part. Each sampling operation is carried out by immersing the pipette tip into the liquid to be sampled and then drawing up the liquid with the syringe. The sampled quantity is checked by means of a micrometric screw fitted to the syringe.
It is obvious that the operation of such equipment requires numerous handling operations remotely performed by the operator, e.g. with the aid of a remote manipulator or invaginated gloves in the wall of the cell. Thus, to the handling operations necessary for performing the sampling operation are added the need to rinse the glassware and wipe the outside of the pipette after each sampling operation. Therefore this equipment is difficult to use when relatively closely spaced periodic sampling operations have to be carried out on an industrial installation.
In addition, the glassware must be frequently replaced and the equipment must incorporate devices making it possible to unplug and replug the bottles.
Finally, the volumes supplied are imprecise, because they are in particular dependent on the delivery speed of the liquid, the viscosity of the solution, the cleanness of the glassware and the adjustment of the meniscus to the calibration mark of the pipette.
Furthermore, the presently available conveyors for automatically passing samples in front of various stations cannot be used within a glove box or a shielded enclosure, as required by the nuclear industry.
Thus, the installations used in confinement cells must be subdivided into a mechanical part located within the cell and a control part located outside, which is not possible with existing conveyors.
Moreover, all existing conveyors have mechanisms which cannot be used in a radioactive medium without undergoing significant modifications. This also applies to the materials forming these mechanisms and which are usually incompatible with a radioactive environment.
Finally, the existing automatic conveyors have excessive dimensions to permit their integration into the cell in which the available volume is limited. Moreover, their cost is very high, if account is taken of the fact that an installation in a confinement cell containing radioactive products has to be periodically replaced.